Laboratory centrifuges consist of a housing that is closable with a cap, in which a rotor connected to an electric drive unit is suspended in such manner that it is able to oscillate. The peripheral region of the rotor is furnished with a series of holders, into which receptacles intended as containers for a substance mixture that is to be centrifuged may be placed. The rotor is further equipped with a rotor hub, by means of which it may be fitted onto a drive shaft inside the housing. Centrifuging must often be carried out under certain thermal conditions, taking into account the chemico-physical properties of the substance mixture, so the interior space of the rotor and housing must be in a correspondingly conditioned state. It is known to equip such centrifuges, more particularly the housings thereof, with corresponding heating and/or cooling systems, particularly including a refrigerant circuit. However, in order to obtain constant thermal conditions for the rotor, the interior of the centrifuge and the substance mixture to be treated, it is also necessary to implement particular structural measures, which are relatively expensive.